1. Field of the Invention
The present invention relates to a method and an apparatus for charging a battery using a solar cell. More particularly, the present invention relates to a method for charging a battery using a solar cell capable of charging a battery with maximum power of the solar cell to maximize charging efficiency, and an apparatus thereof.
2. Description of the Related Art
In recent years, with the significant development of information, communication, and semiconductor technology, supply and use of all types of portable terminals have rapidly increased. More particularly, recent portable terminals have developed to a mobile convergence stage including traditional unique fields and other terminal fields. A mobile communication terminal is a portable terminal that provides various functions, such as a TV viewing function (e.g., mobile broadcasting, such as Digital Multimedia Broadcasting (DMB) or Digital Video Broadcasting (DVB)), a music playing function (e.g., a Motion Pictures Expert Group (MPEG) Audio Layer-3 (MP3)), a photographing function, and an Internet access function as well as a communication function, such as voice call or message transmission/reception.
As mobile communication terminals provide various functions, battery life becomes an important factor. However, there is a limitation on increasing the battery life due to a miniaturized characteristic of a mobile terminal. To address this problem, a mobile terminal providing a charging function using a solar cell has recently been provided. However, in a charging method of the related art using a solar cell, the charging current of the battery is constant regardless of an output state of the solar cell. This case deteriorates the charging efficiency. In a charging method and apparatus of the related art using a solar cell, because the battery is not always charged with maximum power of the solar cell, power created from the solar cell may be consumed. A Maximum Power Point Tracking (MPPT) technology tracking maximum solar cells is applicable to the mobile terminal. However, the MPPT technology has problems in that a circuit is complicated and a cost of the mobile terminal is increased due to an additional circuit.
Therefore, a need exists for a method for charging a battery using a solar cell capable of maximizing a charging efficiency, and an apparatus thereof.